China is denying charges that its border guards have turned back hundreds of refugees who are fleeing a Burmese government assault on ethnic rebels in northern Burma.

More than 1,000 Kachin villagers have massed near the Chinese border seeking to escape from the fighting, which began late last week. A witness tells VOA that most have been turned back at the border and are now hiding in nearby churches and forests.

The Irrawaddy newspaper, run by Burmese exiles in Thailand, quoted local relief workers saying only 200 of the refugees have been admitted into China. It said most of those were elderly or mothers with children, and that Chinese authorities had confiscated any mobile phones and ordered them not to contact anyone in China.

But at a briefing Thursday in Beijing, spokesman Hong Lei said the situation described by the media “does not exist.” He said some Burmese have crossed the border to find relatives and friends, and that the government has provided assistance “in accordance with normal practice.”

On Wednesday, the U.S. Campaign for Burma, a Washington-based rights group, called on world governments to pressure China to provide protection and refuge to the villagers and to let humanitarian organizations reach them.

The Thailand-based Kachin News Group, which has close ties to the rebels, reports that the refugees fear they will be pressed into service as porters for Burmese forces in their fight with the Kachin Independence Army. It said there were about 1,500 villagers in the area by Wednesday and that more were arriving daily.

The fighting has been centered around two hydroelectric dam projects on the Taping River which are being built by Chinese companies and are expected to provide China with electricity.

More than 100 Chinese engineers and construction workers are also reported to have fled back to China from the dam sites since the fighting began. KIA spokesmen say the rebels have blown up three bridges in the area in an effort to impede the Burmese army's advance.

The Kachin News Group says the fighting between the government and KIA forces has spread into Shan state, where a separate ethnic army was already under attack by Burmese forces. The news organization said two KIA battalions have been engaged with Burmese forces since Tuesday evening in northern Shan state and that the fighting continued Wednesday.

Burmese officials have not made any statements regarding the clashes. It is almost impossible for outsiders to confirm reports about the fighting. The border areas are largely off limits to foreigners and journalists.

The Kachin Independence Army, like several other ethnic militias in Burma, signed a cease-fire agreement with the central government several years ago. But those agreements began to break down in 2009, when Burma demanded that the militia groups come under central authority and serve as part of a national border guard. That prompted some militias to resume fighting.